Add 15/2 and 54/21, Solve 7 1/2 + 2 12/21 as a fraction

Add 15/2 and 54/21

1^st number: 7 1/2, 2^nd number: 2 12/21

15/2 + 54/21 is 141/14.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 2 × 21 = 42,
15/2 = 15 × 21/2 × 21 = 315/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
54/21 = 54 × 2/21 × 2 = 108/42
Add the two like fractions:
315/42 + 108/42 = 315 + 108/42 = 423/42
423/42 simplified gives 141/14
So, 15/2 + 54/21 = 141/14
In mixed form: 101/14

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